1. Field of the Invention
The present invention relates to a method of fabricating a micro device and a method of manufacturing a mold for molding the micro device, and more particularly, to a method of fabricating a micro device and a method of manufacturing a mold for molding the micro device, wherein an array of rods in the order of micron can be mass-produced through injection molding and the characteristics of the micro device can be improved by forming the rods with suitable geometry.
2. Description of the Prior Art
Generally, a micro device made of ceramic materials has been employed in a micro sensor, a micro actuator, a micro transducer and the like.
A method of fabricating such a micro device is shown in FIGS. 1a to 1d. 
First, a PZT (Pb(ZrxTi1−x)O3)-sintered plate 11 having a thickness of 800 μm to 1000 μm is prepared as shown in FIG. 1a. The plate 11 is diced by a depth of 300 μm to 600 μm from a top surface of the plate in x and y directions with a dicing wheel 10, so that a plurality of PZT rods 12 are formed on the PZT-sintered plate 11 (see FIG. 1b).
Epoxy 13 is filled into spaces between the PZT rods 12 in such a manner that top surfaces of the PZT rods 12 are exposed from the epoxy 13 (see FIG. 1c).
In order to cause bottom surfaces of the respective PZT rods 12 to be exposed to the outside, the PZT-sintered plate 11 supporting the PZT rods 12 is removed through a polishing process (see FIG. 1d).
The width and length of each of the PZT rods 12 constructed as such are about 100 μm to 200 μm, respectively. The height thereof is about 300 μm to 600 μm, and an interval between the adjacent rods is about 40 μm to 100 μm.
Therefore, the PZT-sintered plate is diced with the wheel, and thus, a micro device having the PZT rods in the order of micron is completed.
In addition, if electrodes are formed on the exposed top and bottom surfaces of the PZT rods, the micro device can be used as an actuator or transducer.
FIG. 2 shows an operating state of a general micro device. The epoxy is filled into spaces between a plurality of PZT rods in the order of micron, and electrodes 14, 15 are formed on the top and bottom surfaces of the plurality of rods. When an alternating voltage is applied to the electrodes 14, 15 from an alternating power supply 16, the micro device is operated as the actuator or transducer.
Alternatively, such a micro device may be used as a sensor for detecting ultrasonic waves.
Since the rods in the order of micron are formed by the dicing wheel in the conventional method of fabricating the micro device described above, it takes considerable working time to form a large number of rods. Thus, it is impossible to mass-produce the micro device.
Furthermore, although the characteristics of the micro sensor, the micro actuator and the micro transducer vary depending on the geometry of the rods, only the rods taking the geometry of an uniform square pillar can be obtained in the process performed by the dicing wheel. Thus, the characteristics of the micro device cannot be further improved.